1. Field of the Invention
The present invention relates to a cooling structure for a rackmount-type control device and a rack-type storage control device.
2. Description of the Related Art
A storage control device comprises a storage section in which a multiplicity of disk drives are connected in the form of an array and provides a host computer (‘host’ hereinbelow) such as a server with logical storage regions (logical volumes). In order to increase reliability and so forth, the storage control device provides a host with a RAID (Redundant Array of Independent Disks)-based redundant storage region.
A controller, a multiplicity of disk drives and power-related devices, which are housed in the enclosure of the storage control device, each generate heat. Hence, it is necessary to cool the controller, disk drives, and power-related devices respectively. In cases where the interior of the enclosure is air-cooled by means of a large-scale cooling fan device, it is difficult to uniformly air-cool the respective parts of the cooling target (which are the controller, disk drives, and power-related devices). In order to adequately cool the respective parts of the cooling target, a stronger cooling fan must be provided, which results in an increase in fabrication costs and electricity charges, and so forth.
Therefore, a storage control device that is constituted such that the storage control device is divided into a plurality of regions which are, namely, a NAS (Network Attached Storage) header mount region, a logic substrate mount region, and a power-source mount region and such that cooling is performed by providing individual cooling mechanisms in each of the regions has also been proposed (Japanese Application Laid Open No. 2007-156751).
The conventional technology that appears in Japanese Application Laid Open No. 2007-156751 relates to a so-called large-scale storage control device and, therefore, cannot be applied as is to a rack-type storage control device. A large-scale storage control device comprises a cooling passage that allows a cooling air stream to pass from top to bottom at the center of the enclosure. However, a rack-type storage control device does not comprise a central cooling passage of this kind.
In addition, in the case of the conventional technology that appears in Japanese Application Laid Open No. 2007-156751, a cooling hole must be provided in the connection substrate in order to guide the cooling air stream into the central cooling passage. Hence, the surface area that can be used for electrical connections of the total surface area of the connection substrate is reduced and it is therefore difficult to more densely mount a greater number of substrates and devices.